Safety appliance for elevators.



No. 744,568. PATENTED NOV. 17, 1903. 1

W. LASAE.

SAFETY APPLIANCE FOR ELEVATORS.

APPLICATION FILED JUNE 15, 1903.

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iatented fi'ovember 17, 1903.

PATENT OFFICE.

WALTER LASAR, on ST. LOUIS, MISSOURI.

SAFETY APPLIANCE FOR ELEVATORS.

SPECIFICATION forming part of Letters Patent N 0. 744,568, datedNovember 17, 1903. Application filed June 15, 1908. Serial No. 161,409.(No model.) I 1 T0 on whom it may, concern:

Be it known that I, WALTER LASA-R, a citicity of St. Louis and State ofMissouri, have invented a new and useful Safety Appliance for Elevators,of which the following is a specification.

My invention relates to elevators, and has for its principal objects toprevent the descent or ascent thereof becoming too rapid and to hold thecar in case the hoisting-cable should break.

The invention consists principally in making the track or rail for thesafety-clutch or guide-shoe so that it may be crimped laterally when theclutch is applied, but will resume its normal position when theclutch isreleased.

It also consists in the parts and in the arrangeinents and combinationof parts hereinafter described and'claimed.

In the accompanying drawings,which form part of this specification, andwherein like symbols refer to like parts wherever they occur, Figure 1is a diagrammatic elevation of an elevator system embodying myinvention. Fig. 2 is a horizontal section of said system on the line 2 2of Fig. 1. Fig. 3 is ahorizontal sectionthereof on the line 3 3 ofFig. 1. Fig l is a detail View of the centrifugal clutch, and Fig. 5 isa cross-sectional viewof one form of guidetrack or rail for thelocking-clutch, and Fig. 6 is a similar view of a modified form thereof.Fig. 7 is a sectional view ofthe clutch-releasingdevice.

The elevator car or platform 1 is located in an ordinary elevator-shaftand is provided or spaces them. In the construction illustrated in Fig.5 the base-plate 3 has two parallel ribs 5 extending longitudinallythereof and integral therewith, and said ribs are made sufficiently thinand resilient to crimp or yield to the pressure of the clutches appliedtransversely thereto, as hereinafter described. zen of the UnitedStates, and a resident of the The elevator car or platform 1 has journalhangers 6 fixed to the bottom thereof, in which is journaled ashaft 7, which is screwthreaded in opposite directions at its respectiveends. threaded nut 8 working thereon. mediate portion of each nut 8 isreduced in diameter and flattened. at opposite sides, ;whereby the endportions of the. nut consti- Each of the threaded ends has a Theintertute shoulders. Over the flat portion of the The other end of thethe nut said lever prevents the nut Sfrom turning on the shaft 7, sothatthe turning of the shaft causesthemovement of the nut lengthwise of theshaft. This endwise move- 7 ment of the nut causes the lever 9 to turnupon its fulcrum, and the turning of the lever causes its outer end tobear transversely against the resilient rib 5 or 5 of the guide track orrail. The pressure of the lever against the resilient rib crimps ordeflects 'from its normal vertical plane the portion of the resilientrib close to the end of the'leverw as well as the part directly oppositethereto. In like manner the second rib is deflected by being jammedagainst the abutment-plate 10 provided therefor. In consequence of thelever 9 and the abutmentpiece 10 (which together constitute asafety-clutch).thus pinching toward each other the portion of theresilient ribs immediately adjacent to them and the adjacent faces ofthe leverand of the abutment-piece thereby being'closer together thanthe normal distance between the outer faces of the respective ribs thefurther descent or ascent of the elevator-car necessitates thecontinuous bending or crimping of the ribs from the point wheretheclutch is first set to the point where the elevator stops.

The force thus applied to stop the elevatorcar is not only the frictionbetween the clutches and the guide-tracks or rails, (which is commonlyrelied upon,) but the resistance of the resilient ribs to the continuouscrimping thereof. This last-mentioned force is particularlyady'antageous on account of the fact that in ordinary elevatorconstruction the guide track or rail is usually covered with grease orotherwise lubricated.

The clutch-operating shaft 7 is operated by any suitable mechanismarranged to be set in operation automatically whenever the elevator-caracquires too rapid a speed, whether ascent or descent. For instance, asshown in the drawings, the clutch-operating shaft 7 has a sheave or drum11, around which passes an endless rope 12. This rope 12 passes from thedrum 11 around a pulley 13, mounted on the bottom of the platform 1, andthence over a pulley 1st, journaled at the top of the elevator-shaft,and thence over pulleys 15 16 16 at the bottom of the shaft, and thenceto the drum 11. The pulley 14 at the top of the elevator-shaft has pawls17 pivotally mounted thereon and arranged to cooperate with a stationaryhousing 18 provided therefor. Said pawls 17 are normally held towardtheir shaft or spindle by means of springs 1.); but when its speedbecomes too great the centrifugal force causes the ends of said pawls tostrike against the stationary housing 18, and thereby stop the movementof the pulley 14 at the top of the elevator-shaft. hen the pulley 14: atthe top of the elevatorshaft stops turning, the tension on the endlessrope 12 increases very greatly. In the normal operation of the parts theforce required to drive the clutch-operating shaft 7 is much greaterthan the force required to drive the several pulleys; but when theuppermost pulley is locked by the pawl 17 the force required to drag therope around said pulley 14- exceeds the force required to drive theclutchoperating shaft. It results from this arrangement that when thetopmost pulley is locked the rope, which normally runs about the severalpulleys, but is stationary around the drum 1]., becomes stationaryaround the pulleys and runs around the drum. Consequently the rope turnsthe drum 11 and with it the clutch-operating shaft 7, so as to set theclutches against their guide tracks or rails. The clutch-operating shaftis shown threaded, so as to set the clutches upon too rapid descent ofthe car; but it is obvious that by reversing the direction of thethreads on the shaft too rapid ascent of the car may be providedagainst.

Preferably the elevator-car is provided with a tooth or projecting lug20 on eachside in position to slide up and down in the space between thelongitudinal ribs 5 and 5 of the guidetrack, and thereby not only guidethe car, but keep the space free from pieces that might prevent theproper crimping of the ribs. For the latter purpose this space may beclosed with wood or other compressible material.

from its engagement.

Obviously the construction hereinbef ore described admits ofconsiderable modification without departing from my invention and I donot wish to be restricted to said construction. Obviously also anysuitable device 21 may be mounted on the car forreleasing the clutch Forinstance, the car may have a hand-lever 22, provided with a pawl 23,arranged to actuate a ratchet-wheel 21L, fixed to the clutch-operatingshaft.

The lever22 is enlarged at its lower end and loosely surrounds theclutch-operating shaft. It is hollowed out and receives within it thepawl-ring 25, upon which the pawls are mounted and which surrounds theratchet-wheel 24, fixed to the clutch-operating shaft. The pawl-ring isprovided with a number of indentations 26, which receive the end of therod 27, which is inserted in the hollow lever-arm 22. Normally the rod27 is withdrawn and the pawl-rin g is free to rotate within the chamberin the lower end of the lever 22; but when it is desired to operate theclutch-operating shaft to release the clutch the rod 27 is inserted andlocks the pawl-ring and the lever 22, and the device operates as thoughthe pawls were mounted directly upon the lever.

hat I claim is 1. In an elevator construction, a car, a guide engaged bysaid car and having a resilient rib, and a clutch on said car to engageand crimp said resilient rib.

2. In an elevator construction, a safety appliance comprising a clutch,and a track therefor, said track comprising abase and two 1011-gitudinal parallel ribs thereon arranged to b criniped by said clutch.

3. In an elevator construction, a safety appliance comprising a clutchon the car, and a track therefor, said track comprising a T- bar and tworesilient plates mounted on opposite sides of the rib of said bar.

4t. In an elevator construction, a safety appliance comprisingaclutclnand atrack therefor, said track comprising a base and twolongitudinal parallel ribs thereon arranged to be crimped by saidclutch, and a lug on said car projecting into the space between saidribs.

5. An elevator construction comprising a car, a guide engaged by saidcar and having a resilient rib, a clutch on said car arranged to engageand crimp said resilient rib, and automatic means for operating saidclutch.

6. An elevator construction comprising a car, a clutch therefor and atrack having a resilient member arranged to be crimped by said clutch,said clutch comprising an abutment-piece and a lever opposite the sameand means for actuating said lever, said means comprising a threadedshaft, a nut on said shaft arranged to engage said lever, a winding-drumon said shaft, and an endless rope arranged to normally move with theelevator and to bind when the car moves too fast.

7. A11 elevator construction comprising a car, a clutch thereoncomprising a lever, a f the drum, and a track for said clutch, saidthreaded shaft, a nut working on said shaft track comprising aresilientmember arranged :o andengaging said lever, and means for actuto beerimped thereby.

ating said shaft, said means comprising a drum on said shaft, a pulley0n the stationary WALTER LASAR' portion, an endless rope winding aboutsaid \Vitnesses: drum and said pulley to stop the same auto- JAMES A.CARR, matically and thereby cause the turning of JULIA B. MEGOWN.

